测定尿中痕量碘的高锰酸钾-亚砷酸体系催化光度法

Catalytic Spectrophotometric Determination of Trace Iodide in Urine with Potassium Permanganate-Arsenious Acid System

在硫酸和磷酸的介质中 ,碘离子催化高锰酸钾与亚砷酸反应生成的锰(Ⅲ)氧化亚砷酸的反应 ,据此建立了催化光度法测定痕量碘的新方法。该法的检出限为0.4μg/L ,测定的线性范围为1.0～25.0μg/L。应用该法测定了尿样中痕量碘的含量 ,获得了满意的结果 ,测定样品的相对标准偏差 (n=6)为2.5%～3.7 %,加标回收率为96.4 %～102.6 %。

The oxidation of arsenious acid by Mn(Ⅲ) which is produced from the reaction of potassium permanganate and arsenious acid can be catalyzed by iodide in the medium of sulphuric acid and phosphoric acid. Based on the catalytic role of iodide, a catalytic spectrophotometric method for the determination of trace iodide has been established with a detection limit of 0.4 μg/L, linear range of 1.0～25.0 g/L, RSD of 2.5%～3.7%(n=6), and recovery rate of 96.4%～102.6%. The method has been satisfactorily used for the determination of iodide in urine samples.